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21.
We present the fourth known case of endometrial carcinoma, and the second case of endometrial small-cell carcinoma, to be associated with paraneoplastic retinopathy. Initial symptoms were decreased visual acuity and a narrowing of the visual field. Endometrial carcinoma was diagnosed several months later. An antibody to 34-kDa bovine retinal antigen was detected in the patient's serum. Thus, autoimmunity was suspected as the cause of the retinopathy. In patients with endometrial carcinoma with visual disturbance of unknown cause, paraneoplastic retinopathy should be suspected.  相似文献   
22.
We report a case of advanced gallbladder cancer in a 37-year-old man who presented in June 1993 with malignant obstructive jaundice. After percutaneous transhepatic biliary drainage and several diagnostic imaging examinations, the patient underwent laparotomy under a diagnosis of extremely advanced gallbladder cancer involving the confluence of the hepatic ducts. The tumor, however, was judged to be unresectable because of its massive spread into the liver along Glisson's sheath, and because of histologically proven peritoneal dissemination. After exploratory laparotomy, one course of anticancer chemotherapy (cisplatin, 100 mg/body IV, on day 1, and 5-fluorouracil, 1000 mg/body, on days 1–5, by continuous infusion) was administered and the completely obstructed hepatic duct was dramatically re-canalized. Four courses of chemotherapy were administered over a 16-month period until jaundice recurred. For these 16 months, the patient's quality of life was well maintained without biliary drainage. He died of increased peritoneal dissemination approximately 2 years after the first course of anticancer chemotherapy.  相似文献   
23.
OBJECTIVE: We aimed to determine whether or not the potential distribution of the sympathetic skin response (SSR) on the palm and dorsum of the hand can be described by an equivalent current dipole (ECD) as an SSR source model. METHODS: The SSR of 22 normal subjects were simultaneously obtained from two electrodes placed on the palm and the dorsum of hand, with an indifferent electrode on the thumbnail. We then measured the SSR potential distribution in 10 of the 20 subjects who had responded to stimulation with a clear dorsal SSR. To do this, 18 electrodes were attached to the palm and dorsum of the hand. SSR-evoking stimulation (sound, voice and rapid inspiration) were randomly delivered to the subject at time intervals of more than 1min to minimize the habituation effect. We estimated the ECD from the measured potential distribution. RESULTS AND CONCLUSIONS: The SSR-evoked by stimulation was negative in potential at the palmar sites of all 22 subjects, and was positive in potential at the dorsal sites of the hand in 20 of the 22 subjects. The SSR potential distribution, which was measured in 10 subjects, reached its maximum negative and positive potential near the base of the middle finger on the palm, and near the corresponding site on the dorsum of the hand, respectively. The SSR potential measured on the dorsum of the hand, however, was about 1/3 in amplitude of those on the palmar sites. These results suggest that the SSR source is located on the palm (probably the sweat glands) as confirmed by the estimated ECD (a negative pole on the palm and a positive pole on the dorsum of the hand). We speculate that the SSR may result from the potential difference caused by the Na(+) concentration gradient in the sweat, which results from intracanal reabsorption of Na(+). SIGNIFICANCE: The ECD resulting from the Na(+) concentration gradient within the canal of sweat glands is thought to be the source of the SSR from the negative pole on the palm to the positive pole on the dorsum.  相似文献   
24.
Background. A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-μm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures.

Methods. Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator.

Results. Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O2 and CO2 transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability.

Conclusions. This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.  相似文献   

25.
This paper studies global bifurcation structure of the chaotic neural networks applied to solve the traveling salesman problem (TSP). The bifurcation analysis clarifies the dynamical basis of the chaotic neuro-dynamics which itinerates a variety of network states associated with possible solutions of TSP and efficiently ‘searches’ for the optimum or near-optimum solutions. By following the detailed merging process of chaotic attractors via crises, we find that the crisis-induced intermittent switches among the ruins of the previous localized chaotic attractors underly the ‘chaotic search’ for TSP solutions. On the basis of the present study, efficiency of the ‘chaotic search’ to optimization problems is discussed and a guideline is provided for tuning the bifurcation parameter value which gives rise to efficient ‘chaotic search’.  相似文献   
26.
Abstract: We report a case of glucagonoma syndrome with liver metastasis, who responded completely to dacarbazine chemotherapy. A 77-year-old woman complained of itching skin eruptions (diagnosed as necrolytic migratory erythema) and weight loss. She was found to have glucose intolerance, anemia, hypoproteinemia and hyperglucagonemia. Abdominal CT and celiac arteriography showed a hypervascular tumor in the pancreatic tail and a metastatic tumor in the left hepatic lobe. Immunohistochemical examination of the metastatic liver tumor obtained by laparoscopic biopsy revealed the tumor cells to be positive for glucagon. The patient was treated with 20 courses of 300 mg/day intravenous dacarbazine for 5 consecutive days followed by a 4 week drug-free interval. No major side effects were noted. Treatment resulted in disappearance of the skin lesions and correction of anemia, glucose intolerance, hypoproteinemia and hyperglucagonemia. Follow-up abdominal CT showed complete resolution of both the primary pancreatic tumor and the metastatic liver tumor. We suggest that dacarbazine be considered as the treatment of choice for metastatic glucagonoma.  相似文献   
27.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
28.
The relationship between the age and the spread of analgesia from different epidural anesthetic doses was examined by studying analgesic dose responses in cervical epidural analgesia. Two different anesthetic doses (5ml or 10ml) of 2% mepivacaine were injected into the cervical epidural space at a constant pressure (80mmHg) using an intravenous apparatus, and the spread of analgesia to pinprick was assessed. The significant correlation was found between the patients age and the number of spinal segments blocked (5ml:r = 0.8498, P < 0.01, 10ml:r = 0.5988, P < 0.01). The inverse linear relationship was found between the patients age and the segmental dose requirement (5ml:r = –0.6754, P < 0.01, 10ml:r = –0.5784, P < 0.01). Patients under 39 years of age showed a direct relationship between the dose injected and the number of spinal segments blocked, enabling prediction of the number of segments blocked with a given dose of local anesthetic. Doubling the epidural dose approximately doubled the number of spinal segments blocked. The analgesic dose-response relation in patients over 60 years of age differed from that in patients under 39 years of age and doubling the epidural dose did not double the number of spinal segments blocked. Progressively more extensive analgesia was obtained from a given dose of local anesthetic with advancing age. It was difficult to limit the extent of analgesia by injecting a smaller dose of local anaesthetic in the elderly.(Hirabayashi Y, Matsuda I, Inoue S et al.: Analgesic dose-response relation in cervical epidural block. J Anesth 2: 22–27, 1988)  相似文献   
29.
T-Cell Regulation in Autoimmune Thyroiditis   总被引:12,自引:0,他引:12  
  相似文献   
30.
Human endometrial stromal cells (ESC) can produce a variety of chemokines, especially after inflammatory stimulation. Interferon-gamma-inducible protein-10 (IP-10) is a potent chemoattractant for lymphocytes, and belongs to the family of non-ELR CXC chemokines. The expression of IP-10 in ESC after stimulation with interferon-gamma (IFN-gamma), interleukin-1 beta (IL-1 beta), tumour necrosis factor-alpha (TNF-alpha), or lipopolysaccharide (LPS) was evaluated using an enzyme-linked immunosorbent assay and Northern blot analysis. A small amount of IP-10 protein was detected in the culture media of unstimulated ESC. The expression of IP-10 mRNA was detected in ESC. IFN-gamma, IL-1 beta, TNF-alpha and LPS significantly stimulated the expression of IP-10 mRNA and protein in ESC. These results suggest that the production of IP-10 by ESC is regulated by inflammatory mediators. The modulation of IP-10 concentrations in the local environment may contribute to the normal and pathological processes of human reproduction by regulating leukocyte trafficking in the endometrium.  相似文献   
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